Conductive rubber composition, conductive rubber and preparation method and application of conductive rubber

Abstract

The invention relates to the field of rubber, and discloses a conductive rubber composition, conductive rubber and a preparation method and application thereof. The rubber composition comprises base rubber, a carbon-based filler and an organic non-polar solvent which are stored independently, the base rubber is a thermoplastic elastomer, and the carbon-based filler is graphene; on the basis of the total weight of the rubber composition, the content of the basic rubber is 95-99.9 wt%, and the content of the carbon-based filler is 0.1-5 wt%. As the carbon-based filler in the rubber composition has high dispersibility, the rubber composition can have lower volume resistivity by filling a small amount of the carbon-based filler, and has lower material cost.

Description

Technical Field

[0001] The invention relates to the field of rubber, and in particular to a conductive rubber composition and conductive rubber, and a preparation method and application thereof. Background Art

[0002] The volume resistivity of conductive rubber materials ranges from 10 2 Ω·m~10 6 Ω·m, conductive rubber materials are widely used in various types of pressure sensors. Piezoresistive sensors have attracted widespread attention due to their simple device structure, low energy consumption, large sensitivity coefficient, good frequency response, etc. Among them, conductive rubber sensors often replace metal material piezoresistive sensors and inorganic conductive material piezoresistive sensors due to their advantages of conductive function, low density, corrosion resistance, and conductivity that can be adjusted within dozens of orders of magnitude, and are widely used in production and life.

[0003] CN105670297A discloses a conductive rubber material for a flexible sensor, a preparation method and an application thereof, wherein the conductive rubber material for a flexible sensor comprises the following components in the following weight proportions: 100 parts of a silicone rubber matrix, 5-100 parts of a conductive filler, 5-30 parts of a modified white carbon black, and 0.1-10 parts of a coupling agent, and the conductive rubber material is prepared by dispersing the conductive filler in a rubber material and cross-linking it by electron beam or gamma ray radiation. The silicone rubber matrix comprises a molecular main chain structure composed of alternating silicon atoms and oxygen atoms, and further, the silicone rubber matrix is ​​at least one of dimethyl silicone rubber, methyl vinyl silicone rubber, methyl vinyl phenyl silicone rubber, phenylene silicone rubber, fluorosilicone rubber, nitrile silicone rubber, and borosilicate rubber. The conductive filler is at least one of conductive carbon black, nanographite, carbon nanotubes, silver-plated powder, nickel powder, and nickel-plated powder. The resistivity of the conductive rubber material is in the range of 2.0×10 3 Ω·m to 1.0×10 10 Ω·m. In this patent, the conductive rubber matrix uses expensive silicone rubber, the conductive filler uses conductive carbon black, metal powder, etc., and the processing method uses a melt compound method. The conductive filler is not easy to disperse efficiently in the rubber matrix, which affects the further improvement of the conductive performance.

[0004] With the popularity of smart products, wearable electronic devices present a huge market prospect, but achieving high sensitivity, high resolution, low-cost manufacturing and complex signal detection of flexible electronic sensors is still a great challenge. As one of the main core component materials of sensors, the breadth of the adjustable resistivity range of conductive rubber materials and factors such as manufacturing costs will affect the future development of wearable devices. In addition, as a sensor in close contact with human skin, its material needs to be selected with little odor and does not contain substances that produce allergic reactions with the skin. Therefore, it is necessary to propose a method for preparing a conductive rubber composition that can solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem in the prior art that conductive fillers are not easy to disperse efficiently in a rubber matrix, which affects the further improvement of conductive performance, and the defect that a large amount of expensive conductive fillers need to be filled to prepare a low-resistivity rubber material in the prior art. A conductive rubber composition and conductive rubber and a preparation method and application thereof are provided. Since the carbon-based filler in the rubber composition has high dispersibility, a small amount of the carbon-based filler can have a lower volume resistivity and a lower material cost.

[0006] In order to achieve the above-mentioned object, the first aspect of the present invention provides a conductive rubber composition, wherein the rubber composition comprises a base rubber, a carbon-based filler and an organic non-polar solvent which are separately stored; the base rubber is a thermoplastic elastomer, and the carbon-based filler is graphene; and based on the total weight of the rubber composition, the content of the base rubber is 95-99.9% by weight, and the content of the carbon-based filler is 0.1-5% by weight.

[0007] A second aspect of the present invention provides a conductive rubber, wherein the conductive rubber is obtained by vulcanizing the conductive rubber composition described above.

[0008] The third aspect of the present invention provides a method for preparing the conductive rubber described above, wherein the method comprises:

[0009] (1) dispersing a carbon-based filler into an organic non-polar solvent to form a suspension containing the carbon-based filler;

[0010] (2) mixing the suspension with a base rubber, and contacting the obtained mixture with a flocculant to precipitate a graphene-modified base rubber mixture containing a volatile solvent, and then drying and vulcanizing to obtain a conductive rubber.

[0011] A fourth aspect of the present invention provides a use of the aforementioned conductive rubber in preparing a flexible resistance sensor.

[0012] Through the above technical scheme, the present invention efficiently disperses the carbon-based filler in the base rubber by a solution compounding method, and the base rubber is a thermoplastic elastomer, so that the rubber composition has excellent conductive properties. Its volume resistivity ranges from 1×10 -2 Ω·m to 1×10 4 Ω·m, which can meet the needs of conductive rubber materials for flexible piezoresistive sensors of wearable devices (10 2 Ω·m to 10 6 Ω·m). At the same time, the rubber composition matrix of the present invention adopts a relatively cheap styrene-butadiene-styrene triblock copolymer (SBS) thermoplastic elastomer instead of a commonly used expensive rubber matrix such as silicone rubber. Due to the efficient dispersion technology of the conductive filler, a small amount of conductive filler can have a lower volume resistivity, so it has a lower material cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the relationship between the volume resistivity and graphene content of the conductive rubbers prepared in Examples 1-8 and the conductive rubber prepared in Comparative Example 1. DETAILED DESCRIPTION

[0014] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0015] As described above, the first aspect of the present invention provides a conductive rubber composition, wherein the rubber composition comprises a base rubber, a carbon-based filler and an organic non-polar solvent which are each independently preserved; the base rubber is a thermoplastic elastomer, and the carbon-based filler is graphene; and based on the total weight of the rubber composition, the content of the base rubber is 95-99.9% by weight, and the content of the carbon-based filler is 0.1-5% by weight.

[0016] The inventors of the present invention have discovered that efficient dispersion of conductive fillers is an important factor in significantly reducing the volume resistivity of rubber materials. If the dispersion effect of conductive fillers is not ideal, a large amount of expensive conductive fillers need to be filled in order to prepare rubber materials with low resistivity, which will undoubtedly increase material costs and affect the mechanical properties of rubber composites.

[0017] The inventors of the present invention found in the process of in-depth research that if the carbon-based filler (graphene) is compounded with the base rubber (thermoplastic elastomer) in an organic non-polar solvent, since most of the carbon atoms in the graphene are sp2 Carbon atoms are non-polar and can be efficiently dispersed in non-polar organic compounds. Styrene thermoplastic elastomer rubbers such as SBS can also be well dissolved in non-polar organic compounds to obtain solutions. Graphene and SBS are dispersed in non-polar organic compounds, which can effectively improve the dispersion effect of graphene in SBS and reduce the volume resistivity of rubber composites at a lower graphene dosage. The thermoplastic elastomer SBS, as the matrix of the conductive elastomer of the flexible resistor sensor, does not require a cross-linking agent to have good elasticity at the operating temperature. The material can also be recycled. Moreover, compared with vulcanized rubber using a cross-linking agent, thermoplastic elastomers such as SBS, as flexible resistor sensor materials, do not have the uncomfortable odor of vulcanizers and accelerators of vulcanized rubber using a cross-linking agent, and are more suitable as sensor materials that are in close contact with the human body. In summary, the SBS graphene conductive composition has incomparable advantages as a flexible resistor sensor material.

[0018] According to the present invention, preferably, based on the total weight of the rubber composition, the content of the base rubber is 95-99.5% by weight, and the content of the carbon-based filler is 0.5-5% by weight; more preferably, based on the total weight of the rubber composition, the content of the base rubber is 95-99% by weight, and the content of the carbon-based filler is 1-5% by weight. In the present invention, if the content of the carbon-based filler is too low, the resistivity will be large and the conductivity will be low, and it cannot be used as a flexible sensor material; if the content of the carbon-based filler is too high, the conductive filler will not be easily dispersed efficiently in the rubber matrix, which affects the further improvement of the conductivity, and the flexibility of the composition decreases, which is not suitable as a flexible sensor material.

[0019] According to the present invention, the organic non-polar solvent is a saturated hydrocarbon solvent, preferably cyclohexane.

[0020] According to the present invention, the content of the carbon-based filler is 0.01-0.7 g, preferably 0.1-0.7 g, and more preferably 0.2-0.5 g, relative to 100 mL of the organic non-polar solvent.

[0021] According to the present invention, the content of the base rubber is 10-70 g, preferably 20-50 g, relative to 1000 mL of the organic non-polar solvent.

[0022] According to the present invention, preferably, the thermoplastic elastomer is a styrene-based thermoplastic elastomer; further, the thermoplastic elastomer is a styrene-butadiene-styrene triblock copolymer (SBS) thermoplastic elastomer; preferably, the content of styrene structural units in the styrene-butadiene-styrene triblock copolymer (SBS) is 35-45% by weight, and the content of butadiene structural units is 55-65% by weight; among the butadiene structural units, the content of 1,2-butadiene structural units is 10-15% by weight, the content of cis-1,4-butadiene structural units is 50-55% by weight, and the content of trans-1,4-butadiene structural units is 30-40% by weight.

[0023] According to the present invention, the number average molecular weight of the styrene-butadiene-styrene triblock copolymer is 1.5×10 5 g / mol to 2×10 5 g / mol, weight average molecular weight is 1.6×10 5 g / mol to 2.2×10 5 g / mol, and the molecular weight distribution index is 1.01-1.2.

[0024] According to the present invention, the graphene is reduced graphene and / or oxidized graphene; the number of graphene layers dispersed in the rubber composition is 1-10 layers; and the highly dispersed carbon-based filler is compounded with the base rubber by solution compounding.

[0025] According to the present invention, the basic structure of the reduced graphene and graphene oxide is a layered carbon atom layer, which is easy to form a conductive network. The conductivity of graphene oxide is further improved after reduction, and the resistivity of the rubber composition is further reduced.

[0026] In the present invention, the ratio of carbon atoms to oxygen atoms in the graphene is C:O=(2-14):1, preferably (6-14):1; the content of C, H, and O elements in the graphene is greater than 98 atomic%, the number of layers of the graphene is 1-10, and the specific surface area is 10-1000m 2 / g, volume resistivity is 10 -6 Ω·m to 10 -5 Ω·m

[0027] According to the present invention, the reduced graphene is different from the oxidized graphene in that the ratio of the number of carbon atoms to the number of oxygen atoms is different.

[0028] In the present invention, the ratio of the number of carbon atoms to the number of oxygen atoms in the graphene oxide is less than 7:1, preferably (3-6):1.

[0029] In the present invention, the ratio of the number of carbon atoms to the number of oxygen atoms in the reduced graphene is greater than 7:1, preferably (8-13):1.

[0030] A second aspect of the present invention provides a conductive rubber, wherein the conductive rubber is obtained by vulcanizing the conductive rubber composition described above.

[0031] According to the present invention, the volume resistivity of the conductive rubber is 10 2 Ω·m to 10 6 Ω·m.

[0032] The third aspect of the present invention provides a method for preparing the conductive rubber described above, wherein the method comprises:

[0033] (1) dispersing a carbon-based filler into an organic non-polar solvent to form a suspension containing the carbon-based filler;

[0034] (2) mixing the suspension with a base rubber, and contacting the obtained mixture with a flocculant to precipitate a graphene-modified base rubber mixture containing a volatile solvent, and then drying and vulcanizing to obtain a conductive rubber.

[0035] According to the present invention, in step (1), the process of dispersing the carbon-based filler into the organic non-polar solvent to form a suspension containing the carbon-based filler is preferably carried out under ultrasonic conditions, wherein the ultrasonic frequency is 2×10 4 Hz to 2×10 5 The carbon-based filler (graphene) is dispersed in an organic non-polar solvent (the organic non-polar solvent is preferably a saturated hydrocarbon solvent, and more preferably cyclohexane), and is fully dispersed by ultrasound to obtain a carbon-based filler (graphene) organic non-polar solvent suspension.

[0036] According to the present invention, in the process of preparing the conductive rubber, the thermoplastic elastomer is in the form of a solution of an organic non-polar solvent containing the thermoplastic elastomer; wherein the solid content of the organic non-polar solvent solution containing the thermoplastic elastomer is 1-20wt%, preferably 2-19wt%.

[0037] According to the present invention, in step (2), the thermoplastic elastomer is in the form of an organic non-polar solvent solution containing the thermoplastic elastomer, and the SBS particles are added to the organic non-polar solvent (preferably cyclohexane) and stirred for 4-24 hours to fully dissolve it.

[0038] According to the present invention, in step (2), the graphene organic non-polar solvent suspension is added dropwise to the dissolved SBS organic non-polar solvent solution in proportion, stirred at a temperature of 40-70°C for 12-24 hours, and stirred sufficiently to make the mixture uniform; preferably, the stirring rate is 50-70rpm, and the stirring reaction is carried out at a temperature of 60-80°C for 0.3-1 hour. Then the obtained mixed solution is poured into an appropriate amount of flocculant (the flocculant is preferably an alcohol substance, more preferably ethanol or isopropanol), and a graphene-modified SBS composition containing a volatile solvent is precipitated, and then the mixture is dried on a double-roll mill at 90-120°C, and a dry graphene-modified SBS composition is obtained by sheeting.

[0039] According to the present invention, in step (2), preferably, the mixing comprises: dropping the suspension into the base rubber at a dropping rate of 1-50 mL / min, more preferably, the delivery rate is 5-15 mL / min.

[0040] According to the present invention, the molding method of the graphene-modified SBS rubber composition is as follows: preheating a flat-plate vulcanizer to a set temperature (150-170° C.), laying the graphene-modified SBS composition sample sheet obtained in the previous step in a 2 mm sheet mold, padding a tetrafluoroethylene plate between the sample and the mold, placing the sample in a flat-plate vulcanizer, preheating for 5-10 minutes, deflation for 2-3 times, half-pressing for 5-10 minutes, deflation for 2-3 times, full-pressing for 5-10 minutes, and then placing the sample in an unheated flat-plate vulcanizer, cooling the mold and the sample to room temperature, and then taking out the sample to obtain a 2 mm thick graphene-modified SBS composition film.

[0041] A fifth aspect of the present invention provides a use of the conductive rubber described above in preparing a flexible resistance sensor.

[0042] The present invention will be described in detail below through examples.

[0043] In the following examples and comparative examples:

[0044] Experimental materials:

[0045] SBS thermoplastic elastomer: industrial product, granular solid, brand 4402, produced by Beijing Yanshan Branch of Sinopec. The content of styrene structural unit in SBS is 40wt%, and the content of butadiene structural unit is 60wt%; in the butadiene structural unit, the content of 1,2-butadiene structural unit is 12wt%, the content of cis-1,4-butadiene structural unit is 35wt%, and the content of trans-1,4-butadiene structural unit is 53wt%, and the number average molecular weight is 1.7×10 5 g / mol, weight average molecular weight is 1.5×10 5g / mol, and the molecular weight distribution index is 1.1. In addition, in the present invention, the antioxidant used in SBS is a compound of antioxidant 264 (4,6-di-tert-butyl-p-cresol) + TNPP (tris-nonylated phenyl phosphite), and the content is 0.8wt%.

[0046] Graphene: powdered sample, produced by Xiamen Kaina Graphene Technology Co., Ltd. The ratio of carbon atoms to oxygen atoms in the graphene is C:O=8.5:1; the content of C, H, and O elements in the graphene is greater than 98 atomic %; the number of layers of the graphene is 5, and the specific surface area is 642m 2 / g, volume resistivity is 6.1×10 -6 Ω·m.

[0047] Cyclohexane and ethanol were purchased from Beijing Inokai Chemical Reagent Company, chemically pure.

[0048] The content of monomer units in SBS was measured by NMR method, and the molecular weight was measured by GPC method.

[0049] Example 1

[0050] Example 1 is used to illustrate the preparation of the rubber composition and the conductive rubber provided by the present invention.

[0051] (1) Under the condition of ultrasonic frequency of 10 kHz, 0.015 g of graphene was dispersed in 300 mL of cyclohexane (density 0.79 g / cm 3 ) and fully dispersed it by ultrasound to obtain a graphene cyclohexane suspension;

[0052] (2) Add 20 g of SBS particles into 1000 mL of cyclohexane and stir at a stirring rate of 60 rpm for 24 hours to fully dissolve them;

[0053] (3) Add the graphene cyclohexane suspension dropwise to the dissolved SBS cyclohexane solution at a drop rate of 5 mL / min, stir and react at 70° C. for 24 hours, and stir thoroughly to mix evenly. Then pour the resulting mixed solution into an appropriate amount of ethanol to precipitate a graphene-modified SBS composition, which is then dried on a double-roll mill at 100° C. to produce a sheet.

[0054] Preheat the flat-plate vulcanizer to the set temperature (165°C), spread the graphene-modified SBS composition sample sheet obtained in the previous step on a 2 mm sheet mold, place a tetrafluoroethylene plate between the sample and the mold, put it into the flat-plate vulcanizer, preheat for 10 minutes, deflate 3 times, half-press for 10 minutes, deflate 3 times, fully press for 10 minutes, then put it into an unheated flat-plate vulcanizer, cool the mold and the sample to room temperature, then take out the sample to obtain a 2 mm thick graphene-modified SBS conductive rubber H1, and leave it for more than 12 hours.

[0055] Wherein, the weight percentage of graphene in the rubber composition in Example 1 to the modified SBS composition is 0.1 wt %.

[0056] Embodiment 2-8

[0057] Conductive rubbers H2 to H8 were prepared in the same manner as in Example 1, except that the weight percentage of graphene in the rubber composition of Examples 2-8 to the modified SBS composition was 0.2wt%, 0.5wt%, 1wt%, 1.5wt%, 2wt%, 3.5wt% and 4.5wt%.

[0058] In addition, the amounts of graphene, cyclohexane and SBS are shown in Table 1.

[0059] Comparative Example 1

[0060] The conductive rubber DH1 was prepared in the same manner as in Example 1, except that the weight percentage of graphene in the rubber composition of Comparative Example 1 to the modified SBS composition was 0 wt %, and the graphene dissolution preparation step (1) in Example 1 was omitted.

[0061] In addition, the amounts of graphene, cyclohexane and SBS are shown in Table 1.

[0062] Table 1

[0063]

[0064]

[0065] Test Case

[0066] The properties of the 2 mm thick graphene-modified SBS conductive rubber prepared in Comparative Example 1 and Examples 1-8 were tested, and the results are shown in Table 2 in terms of volume resistivity.

[0067] The volume resistivity of the conductive rubber was tested using a four-probe resistivity meter (model RTS-8, produced by Anhemeng Technology Development Co., Ltd.).

[0068] Table 2

[0069] Graphene content / wt% Volume resistivity ρ / Ω·m Comparative Example 1 (DH1) 0 <![CDATA[4.0×10 7 ]]> Example 1 (H1) 0.1 <![CDATA[2.3×10 4 ]]> Example 2 (H2) 0.2 <![CDATA[1.0×10 3 ]]> Example 3 (H3) 0.5 12 Example 4 (H4) 1.0 <![CDATA[6.3×10 -1 ]]> Example 5 (H5) 1.5 <![CDATA[3.4×10 -1 ]]> Example 6 (H6) 2.0 <![CDATA[2.0×10 -1 ]]> Example 7 (H7) 3.5 <![CDATA[1.1×10 -1 ]]> Example 8 (H8) 4.5 <![CDATA[8.9×10 -2 ]]>

[0070] in addition, Figure 1 The graph of the relationship between the volume resistivity and the graphene content of the conductive rubber prepared in Examples 1-8 and the conductive rubber prepared in Comparative Example 1 is shown in Table 2 and Figure 1It can be seen that the volume resistivity of graphene / SBS conductive rubber decreases significantly with the increase of graphene content. When the graphene content increases from 0 to 0.5wt% (DH1, H1, H2 and H3), the volume resistivity value decreases by 5 orders of magnitude. When the graphene content increases from 0.5 to 4.5wt% (H3, H4, H5, H6, H7, H8), the volume resistivity decreases slowly. Compared with pure SBS, the volume resistivity of the composition with a graphene content of 1wt% decreases by 8 orders of magnitude. When the graphene content is above 0.1wt%, the SBS graphene composite material can be used for conductive rubber composite materials such as flexible resistive pressure sensors (10 2 Ω·m~10 6 Ω·m) is used.

[0071] The rapid decrease in volume resistivity is because the graphene in the present invention is highly reduced graphene, has good affinity with the non-polar organic solvent cyclohexane, and can be well dispersed in the non-polar SBS matrix during the solution compounding process, so it has a small percolation threshold (0.5wt%) in SBS. When the graphene content is greater than the percolation threshold content, the graphene sheets contact each other to form a conductive network, thereby improving the conductive properties of the SBS composition.

[0072] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A conductive rubber composition, characterized in that: The rubber composition comprises a base rubber, a carbon-based filler and an organic non-polar solvent which are stored independently of each other; the base rubber is a thermoplastic elastomer, and the carbon-based filler is graphene; and based on the total weight of the rubber composition, the content of the base rubber is 95-99.9% by weight, and the content of the carbon-based filler is 0.1-5% by weight.

2. The rubber composition according to claim 1, wherein Based on the total weight of the rubber composition, the content of the base rubber is 95-99.5% by weight, and the content of the carbon-based filler is 0.5-5% by weight.

3. The rubber composition according to claim 1 or 2, wherein: The organic non-polar solvent is a saturated hydrocarbon solvent, preferably cyclohexane; Preferably, the content of the carbon-based filler is 0.01-0.7 g relative to 100 mL of the organic non-polar solvent; Preferably, the content of the base rubber is 10-70 g relative to 1000 mL of the organic non-polar solvent.

4. The rubber composition according to any one of claims 1 to 3, wherein The thermoplastic elastomer is a styrene-based thermoplastic elastomer; Preferably, the thermoplastic elastomer is a styrene-butadiene-styrene triblock copolymer thermoplastic elastomer; Preferably, the content of styrene structural units in the styrene-butadiene-styrene triblock copolymer is 35-45% by weight, and the content of butadiene structural units is 55-65% by weight; Preferably, in the butadiene structural unit, the content of 1,2-butadiene structural unit is 10-15% by weight, the content of cis-1,4-butadiene structural unit is 50-55% by weight, and the content of trans-1,4-butadiene structural unit is 30-40% by weight; Preferably, the number average molecular weight of the styrene-butadiene-styrene triblock copolymer is 1.5×10 5 g / mol to 2×10 5 g / mol, weight average molecular weight is 1.6×10 5 g / mol to 2.2×10 5 g / mol, and the molecular weight distribution index is 1.01-1.

2.

5. The rubber composition according to any one of claims 1 to 3, wherein: The graphene is reduced graphene and / or oxidized graphene; Preferably, the ratio of the number of carbon atoms to the number of oxygen atoms in the graphene is C:O=(2-14):1, more preferably (6-14):1; Preferably, the content of C, H and O elements in the graphene is greater than 98 atomic %; Preferably, the number of layers of the graphene is 1-10; Preferably, the specific surface area of ​​the graphene is 10-1000m 2 / g, volume resistivity is 10 -5 Ω·m to 10 -6 Ω·m.

6. A conductive rubber, characterized in that: The conductive rubber is obtained by vulcanizing the conductive rubber composition according to any one of claims 1 to 5.

7. The conductive rubber according to claim 6, wherein: The volume resistivity of the conductive rubber is 1×10 -2 Up to 1×10 4 Ω·m.

8. A method for preparing the conductive rubber according to claim 6 or 7, characterized in that: The method includes: (1) dispersing a carbon-based filler into an organic non-polar solvent to form a suspension containing the carbon-based filler; (2) mixing the suspension with a base rubber, and contacting the obtained mixture with a flocculant to precipitate a graphene-modified base rubber mixture containing a volatile solvent, and then drying and vulcanizing to obtain a conductive rubber.

9. The method according to claim 8, wherein: In step (2), the mixing conditions include: stirring the reaction at a temperature of 40-70° C. for 12-24 hours; Preferably, the mixing comprises: dropping the suspension into the base rubber at a dropping rate of 1-50 mL / min.

10. Use of the conductive rubber according to claim 6 or 7 in preparing a flexible resistance sensor.

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